Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f9bc08ef3769084ea1dc3672b5f52815c9f9c6fa193eab36c439872fe7eba36' 
  AND token = 'ypFi7S9ThUoHbSwqzrIFPSpih6jM5+o+kWx40XzXXXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}